Well water often contains objectionable impurities such as dissolved iron, manganese, methane gas, or hydrogen sulfide. If the water contains dissolved iron it will tend to oxidize when exposed to air, which causes the iron to precipitate out of solution. These precipitates cause rust-coloured stains, which are difficult to remove from porcelain surfaces such as toilet bowls, sinks and tubs. Methane is undesirable. The hydrogen sulfide is disagreeable because of its characteristic rotten egg odour. It is highly desirable to overcome these two contamination problems. Aeration of well water has been proposed in the past, but the systems available were expensive to install, and required frequent costly maintenance, to remain effective. An example is shown in U.S. Pat. No. 6,287,369 D W Osmund Sep. 11, 2001.
Another problem associated with well water is radon, a naturally occurring, water soluble radioactive gas that results from the breakdown of radium in soil, rock and water.
There are two known methods of treating water contaminated by radon gas, namely, by aeration, and by activated carbon filtration.
The aeration method involves introducing air into the water supply to increase the gas-liquid interface. This allows the contaminants dissolved in the water to diffuse into the gas phase, as disclosed in U.S. Pat. No. 6,287,369.
By similar principles excess methane gas can be displaced from the water and vented to atmosphere in a hazard free manner. This is desirable since methane can fuel biological activity and fouling of plumbing systems, and sulphide production in hot water tanks, as well as being inflammable.
According to Henry's law the infusion of air into the water will displace other gases such as methane, and the air and methane, and other gases, will then be vented to atmosphere.
As the gas mixture is vented from the water supply the recirculated water is ready for use.
In-well aeration contaminant removal systems are typically complex and thus relatively expensive to install and maintain. Therefore, a need exists for an improved in-well aeration system that overcomes the deficiencies of the prior art. More particularly, there is a need in the art for an inexpensive and energy efficient in-well aeration device for removing or releasing contaminants from well water.